It is nothing like any of the BMS systems I have seen since every one of those has required individual wires going to each battery back to the BMS. This system has no wires and all the balancing is done via the on-battery wireless battery module.
At full tilt the charger will do about 10a , it will slow down considerably before it even gets to full charge , so you wont have a problem . Reality is your leaf cells will stay so closely balanced that your bms will hardly come on . once my pack was balanced i would cycle it dozens of time and each cell was identical to 1/100th of a volt , no bms .
If your cells started to drift you might see 4.01v compared to 4.0v . so it wont even matter . With such small variations it requires very small amounts of current to get it back inline . I ran my first USED leaf pack for 2 years and they were still perfectly balanced without a bms . Your setup sounds really cool and i’m looking forward to hearing more about it after you have it for a while .
Have you considered upgrading to a Deltaq charger , many people have done it and it is a great charger . it has multiple charge profiles in it that are user selective at anytime
I currently have a remote/wireless volt/current monitor on my vehicle showing what the Zivan does for Pb. I could use it to monitor the Lithium charging. The wife just came back from a trip in the GEM and I see 11.5A and 76.51V. IIRC it does top out at 84V or so in Pb mode.
Good to know the batteries hardly ever need balancing but it also sounds like it’s a feature of these wireless battery modules. I notice you said 4.0V so I’m guessing you’ve set your peak charge at 4.0v/cell as opposed to 4.1V/cell. I will be figuring out how easy SSI-Racing has made it to change the battery module settings and probably do the same but boy, unlike my RC charge controllers, I get the impression the ‘big’ chargers don’t give us that kind of control of the charging.
I had a DeltaQ on our ZonE 48V and use the funky battery tap,tap mechanism to change the charge profiles. I think there were 11 or so stored profiles i could pick from and had to look at flashing LEDs to get to the correct one. All very crude compared to the RC chargers I’m used to. I’m not against getting a new charger.
I did the first nissan leaf to gem conversion about 5 years ago . charged it to 4.13v and a year later pack had lost a lot of capacity. talked with a battery engineer that worked @ enerdale and he said in all their testing 4.0v made them last much longer than 4.1v . iirc the current setting goes to 4.03v , close enough .
you might want to try your charger you have now . one my 2014 i use the Deltaq set to Gel . turns off at 84.x volts so works well with my LTO pack . i will add lithium profiles to it because want to charge to 88v .
good to know, I will start at 4.0V/80V then. The Zivan is doing the Pb at 86.3V now at 3A for my 6 Pb batteries.
I may look into the temp sensor to see if I can control that voltage but I could also put a relay on the charger and disconnect it at 80V after I make sure all cells have been balanced first.
Hoping to pick up the 5 Gen 4 modules tomorrow.
Currently, even after a full charge, just a mile or so down the road I notice the system performance dropping with the Pb batteries and suspect the voltage is sagging. Hoping that with 80V full charge and higher capacity there will be far less voltage sagging so it’ll remain peppy. After that evaluation I will then look to swapping in a 7.5HP motor and slight controller tweeks to get good 30MPH performance.
The difference between the leaf cells and lead is huge . on a stock 5hp motor with a 10.xx diff and large diam tires it will go over 40mph . to get over 25mph are you reprograming or using a mm ?
Wow, So I’m guessing I really didn’t need the 7.5HP motor… I’ll be due for tires soon so I was thinking of looking for some VW wheels/tires but I have the software to reprogram so that was the route I was planning. It currently will do 25 on flat and decent charge and down hill it governs at 29 so I figure 29/30 should be easy with higher V at the batteries and a flatter discharge curve of lithium.
hmm, looking at the Zivan’s current output voltage while charging, it would seem a 22S(88V) setup would be ideal… @Inwo is that 1/2 Leaf module a Gen 4 chemistry?
I tested Inwo’s 1/2 module it was 100% capacity . a 21s or 22s is perfect .@22s you have a working voltage of 88v - 77v . your gem will never get sluggish . Inwo can get you a 3v spoof and you shouldn’t have any error codes .
one other thing on 2005 plus you can calibrate your dash charge meter to be accurate with this setup
My concern with Inwos 1/2 module was the capacity and nominal voltage since I think those changed when the Gen 4 module was introduced( Nissan Leaf Gen 4 module( 2P4S 14.6V(3.65ea) @ 116.6Ahr ) ).
3 volt spoof? Is that documented anywhere? I’m guessing that 85V is the max input to the T1 so therefore a couple of diode drops are needed on the controller sense line or something?
BTW, I’ve got a 2002 so the controller is: GE 72V 350A - also known as a T1
i think it is the gen3 so not compatible . Also i haven’t over volted a T1 so dont know where the high voltage cutoff is . on T4 it is 85v . you will have to experiment . INWO sells a small device that lowers the line voltage (spoof) and allows us to run higher voltages , works well on my T4 & T5
I think I saved the spec’s/docs on the T1 somewhere and will look at what it says. I do have a small 4A power supply which can go up to 100V so maybe I can disconnect the battery, connect the PS at 80V and slowly turn up the PS until the T1 complains. Thx
Looks like “can” stuff.
3 types of acquisition boards.
Surplus inventory. $???
Current product. Research on line.
Elite Power Solutions EMS Computer
Energy management systems.
I’m thinking less than 1/2 price…
but they show it connected to their battery modules( 4S ) and there are only 4 sensing modules so it sure looks like a 48V system. I’m not sure what the smaller modules are for. The computer has a VIDEO out so a small NTSP display probably shows what’s going on. Not sure how it would be setup/controlled.
